P4 video is "hitchy"

[Yaw Master]

I am a longtime P2 pilot. My new P4 produces good stills, but the video is inadequate. The video below was shot by the P4 in 1080 at 30fps. As I made the slow yaw move, you will see the hitch appear at regular intervals.

So experts, what should I try? Gimbal calibration?

https://www.facebook.com/video.php?v=1289238814468390

Sent from my iPhone using PhantomPilots